There are a number of instances when it is desirable or necessary to test or monitor the concentration of an analyte, such as glucose, lactate, or oxygen, for example, in bodily fluid of a body. Bodily sample analyte tests are routinely conducted in a variety of medical settings (e.g., doctor's office, clinic, hospital, by medical personnel) and in the home by the patient and/or a caretaker. For example, it may be desirable to monitor high or low levels of glucose in blood or other bodily fluid that may be detrimental to a human. In a healthy human, the concentration of glucose in the blood is maintained between about 0.8 and about 1.2 mg/mL by a variety of hormones, such as insulin and glucagons, for example. If the blood glucose level is raised above its normal level, hyperglycemia develops and attendant symptoms may result. If the blood glucose concentration falls below its normal level, hypoglycemia develops and attendant symptoms, such as neurological and other symptoms, may result. Both hyperglycemia and hypoglycemia may result in death if untreated. Maintaining blood glucose at an appropriate concentration is thus a desirable or necessary part of treating a person who is physiologically unable to do so unaided, such as a person who is afflicted with diabetes mellitus.
The most important factor for reducing diabetes-associated complications is the maintenance of an appropriate level of glucose in the blood stream. The maintenance of the appropriate level of glucose in the blood stream may prevent and even reverse some of the effects of diabetes. Certain compounds may be administered to increase or decrease the concentration of blood glucose in a body. By way of example, insulin can be administered to a person in a variety of ways, such as through injection, for example, to decrease that person's blood glucose concentration. Further by way of example, glucose may be administered to a person in a variety of ways, such as directly, through injection or administration of an intravenous solution, for example, or indirectly, through ingestion of certain foods or drinks, for example, to increase that person's blood glucose level.
Regardless of the type of adjustment used, it is typically desirable or necessary to determine a person's blood glucose concentration before making an appropriate adjustment. Typically, blood glucose concentrations are tested in vitro by the diabetic, or sometimes by a physician, periodically and often multiple times each day.
The tools typically used in conventional in vitro self-monitoring of blood glucose levels includes a lancing device having a removable and replaceable cap, a glucose meter, and a container or vial of glucose testing strips. The blood sample is obtained by using the lancing device, for example, to make blood available external to the skin, to obtain the necessary sample volume for in vitro testing. The fresh blood sample is then applied to an in vitro sensor, such as an analyte test strip, which is positioned in the meter, whereupon suitable detection methods, such as calorimetric, electrochemical, or photometric detection methods, for example, may be used to determine the person's actual blood glucose level. Such a glucose monitoring regime typically involves multiple steps, including: (1) locating and opening a test strip vial; (2) removing a test strip and replacing the lid on the vial; (3) inserting the test strip into the meter; (4) coding/calibrating the meter; (5) priming the lancing device; (6) lancing the finger or alternate site; (7) applying blood to the test strip; (8) waiting for the meter to analyze the blood glucose level and provide the test results; and (9) disposing of the used test strip. While such a regime is very effective, the use of a separate glucose meter, lancet and testing strips can be labor intensive and inconvenient. Additionally, with three separate components, use and handling of the system is more cumbersome and requires keeping track of and maintaining multiple components. Moreover, the extensive manual manipulations of such a regime and system make the process susceptible to user error.
As such, analyte meters having lancet mechanism and test strips integrated in a single unit or housing are highly desirable. With such a system, numerous analyte tests may be performed without having to manually load a new test strip for each test performed, or without having to separately handle a lancing device. However, a disadvantage of currently available integrated lancing and testing devices is that they tend to be bulky and relatively heavy, particularly if one or more motors, including one or more batteries sufficient to power the motors, are used to actuate the lancing mechanism and/or to advance a test strip into position to receive a body fluid sample.
Accordingly, it is desirable to have an integrated analyte measurement system which is easy to use and requires minimal steps each time a person tests his or her analyte level (e.g., a person with diabetes tests his or her glucose level), while not sacrificing accuracy, reliability or functionality.